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1.
J Fish Biol ; 100(3): 675-686, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34928507

RESUMO

Throughout the Great Lakes, burbot Lota lota are a native, high-trophic level predator that plays a substantial ecological role. L. lota spawning occurs during wintertime and early spring with length-at-hatch of 3 mm. Wild-caught larval L. lota were obtained from three different locations: Lake Superior Keweenaw Peninsula, Ontonagon, Michigan (LSKP), Lake Michigan Midlake Reef (LMMR) and the St. Clair-Detroit River System (SCDR). Adult spawning L. lota were captured from the Sturgeon River, Pelkie, Michigan (LSSR) and were artificially fertilized; eggs were retained and reared in a laboratory setting. Throughout the first 10 weeks of development, cultured larval L .lota were randomly selected and photographed to measure morphological features. These features were contrasted between cultured larvae and wild-caught larvae to understand developmental variability in L. lota. From patterns discerned in both cultured and wild-caught larval L. lota we demonstrated the importance of asynchronous hatching, source location, and variability in larval L. lota development. Comparisons of wild-caught larval L. lota showed morphological differences, as well as variability in stage and size based on sampling month. These results established that larval L. lota development in the Great Lakes is highly flexible and both species-specific and environmental processes create the observed variability. The impact of this variability on L. lota populations must be explored to further understand this native Great Lakes species.


Assuntos
Gadiformes , Lagos , Animais , Peixes , Larva , Rios
2.
J Chem Inf Model ; 59(11): 4844-4854, 2019 11 25.
Artigo em Inglês | MEDLINE | ID: mdl-31613613

RESUMO

Noble gases are chemically inert, and it was therefore thought they would have little effect on biology. Paradoxically, it was found that they do exhibit a wide range of biological effects, many of which are target-specific and potentially useful and some of which have been demonstrated in vivo. The underlying mechanisms by which useful pharmacology, such as tissue and neuroprotection, anti-addiction effects, and analgesia, is elicited are relatively unexplored. Experiments to probe the interactions of noble gases with specific proteins are more difficult with gases than those with other chemicals. It is clearly impractical to conduct the large number of gas-protein experiments required to gain a complete picture of noble gas biology. Given the simplicity of atoms as ligands, in silico methods provide an opportunity to gain insight into which noble gas-protein interactions are worthy of further experimental or advanced computational investigation. Our previous validation studies showed that in silico methods can accurately predict experimentally determined noble gas binding sites in X-ray structures of proteins. Here, we summarize the largest reported in silico reverse docking study involving 127 854 protein structures and the five nonradioactive noble gases. We describe how these computational screening methods are implemented, summarize the main types of interactions that occur between noble gases and target proteins, describe how the massive data set that this study generated can be analyzed (freely available at group18.csiro.au), and provide the NDMA receptor as an example of how these data can be used to understand the molecular pharmacology underlying the biology of the noble gases. We encourage chemical biologists to access the data and use them to expand the knowledge base of noble gas pharmacology, and to use this information, together with more efficient delivery systems, to develop "atomic drugs" that can fully exploit their considerable and relatively unexplored potential in medicine.


Assuntos
Gases Nobres/metabolismo , Proteínas/metabolismo , Animais , Sítios de Ligação , Bases de Dados de Proteínas , Descoberta de Drogas , Humanos , Simulação de Acoplamento Molecular , Ligação Proteica , Proteínas/química , Proteoma/química , Proteoma/metabolismo , Termodinâmica
3.
Eur J Nucl Med Mol Imaging ; 45(13): 2285-2299, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30259091

RESUMO

BACKGROUND: Effective anticancer therapy is thought to involve induction of tumour cell death through apoptosis and/or necrosis. [18F]ICMT-11, an isatin sulfonamide caspase-3/7-specific radiotracer, has been developed for PET imaging and shown to have favourable dosimetry, safety, and biodistribution. We report the translation of [18F]ICMT-11 PET to measure chemotherapy-induced caspase-3/7 activation in breast and lung cancer patients receiving first-line therapy. RESULTS: Breast tumour SUVmax of [18F]ICMT-11 was low at baseline and unchanged following therapy. Measurement of M30/M60 cytokeratin-18 cleavage products showed that therapy was predominantly not apoptosis in nature. While increases in caspase-3 staining on breast histology were seen, post-treatment caspase-3 positivity values were only approximately 1%; this low level of caspase-3 could have limited sensitive detection by [18F]ICMT-11-PET. Fourteen out of 15 breast cancer patients responded to first-line chemotherapy (complete or partial response); one patient had stable disease. Four patients showed increases in regions of high tumour [18F]ICMT-11 intensity on voxel-wise analysis of tumour data (classed as PADS); response was not exclusive to patients with this phenotype. In patients with lung cancer, multi-parametric [18F]ICMT-11 PET and MRI (diffusion-weighted- and dynamic contrast enhanced-MRI) showed that PET changes were concordant with cell death in the absence of significant perfusion changes. CONCLUSION: This study highlights the potential use of [18F]ICMT-11 PET as a promising candidate for non-invasive imaging of caspase3/7 activation, and the difficulties encountered in assessing early-treatment responses. We summarize that tumour response could occur in the absence of predominant chemotherapy-induced caspase-3/7 activation measured non-invasively across entire tumour lesions in patients with breast and lung cancer.


Assuntos
Azidas , Neoplasias da Mama/tratamento farmacológico , Caspase 3/metabolismo , Caspase 7/metabolismo , Indóis , Neoplasias Pulmonares/tratamento farmacológico , Tomografia por Emissão de Pósitrons , Adulto , Idoso , Neoplasias da Mama/diagnóstico por imagem , Neoplasias da Mama/enzimologia , Ativação Enzimática/efeitos dos fármacos , Feminino , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Processamento de Imagem Assistida por Computador , Neoplasias Pulmonares/diagnóstico por imagem , Neoplasias Pulmonares/enzimologia , Masculino , Pessoa de Meia-Idade
4.
HIV Med ; 17(4): 247-54, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26394818

RESUMO

OBJECTIVES: Following national guidelines to expand HIV testing in high-prevalence areas in England, a number of pilot studies were conducted in acute general medical admission units (ACUs) and general practices (GPs) to assess the feasibility and acceptability of testing in these settings. The aim of this study was to estimate the cost per HIV infection diagnosed through routine HIV testing in these settings. METHODS: Resource use data from four 2009/2010 Department of Health pilot studies (two ACUs; two GPs) were analysed. Data from the pilots were validated and supplemented with information from other sources. We constructed possible scenarios to estimate the cost per test carried out through expanded HIV testing in ACUs and GPs, and the cost per diagnosis. RESULTS: In the pilots, cost per test ranged from £8.55 to £13.50, and offer time and patient uptake were 2 minutes and 90% in ACUs, and 5 minutes and 60% in GPs, respectively. In scenario analyses we fixed offer time, diagnostic test cost and uptake rate at 2 minutes, £6 and 80% for ACUs, and 5 minutes, £9.60 and 40% for GPs, respectively. The cost per new HIV diagnosis at a positivity of 2/1000 tests conducted was £3230 in ACUs and £7930 in GPs for tests performed by a Band 3 staff member, and £5940 in ACUs and £18 800 in GPs for tests performed by either hospital consultants or GPs. CONCLUSIONS: Expanded HIV testing may be more cost-efficient in ACUs than in GPs as a consequence of a shorter offer time, higher patient uptake, higher HIV positivity and lower diagnostic test costs. As cost per new HIV diagnosis reduces at higher HIV positivity, expanded HIV testing should be promoted in high HIV prevalence areas.


Assuntos
Custos e Análise de Custo/métodos , Testes Diagnósticos de Rotina/economia , Infecções por HIV/diagnóstico , Adolescente , Adulto , Idoso , Inglaterra , Medicina Geral/estatística & dados numéricos , Hospitalização/estatística & dados numéricos , Humanos , Programas de Rastreamento/economia , Pessoa de Meia-Idade , Projetos Piloto , Adulto Jovem
5.
Psychol Med ; 46(11): 2435-44, 2016 08.
Artigo em Inglês | MEDLINE | ID: mdl-27305830

RESUMO

BACKGROUND: Relapse is distressingly common after the first episode of psychosis, yet it is poorly understood and difficult to predict. Investigating changes in cognitive function preceding relapse may provide new insights into the underlying mechanism of relapse in psychosis. We hypothesized that relapse in fully remitted first-episode psychosis patients was preceded by working memory deterioration. METHOD: Visual memory and verbal working memory were monitored prospectively in a 1-year randomized controlled trial of remitted first-episode psychosis patients assigned to medication continuation (quetiapine 400 mg/day) or discontinuation (placebo). Relapse (recurrence of positive symptoms of psychosis), visual (Visual Patterns Test) and verbal (Letter-Number span test) working memory and stressful life events were assessed monthly. RESULTS: Remitted first-episode patients (n = 102) participated in the study. Relapsers (n = 53) and non-relapsers (n = 49) had similar baseline demographic and clinical profiles. Logistic regression analyses indicated relapse was associated with visual working memory deterioration 2 months before relapse [odds ratio (OR) 3.07, 95% confidence interval (CI) 1.19-7.92, P = 0.02], more stressful life events 1 month before relapse (OR 2.11, 95% CI 1.20-3.72, P = 0.01) and medication discontinuation (OR 5.52, 95% CI 2.08-14.62, P = 0.001). CONCLUSIONS: Visual working memory deterioration beginning 2 months before relapse in remitted first-episode psychosis patients (not baseline predictor) may reflect early brain dysfunction that heralds a psychotic relapse. The deterioration was found to be unrelated to a worsening of psychotic symptoms preceding relapse. Testable predictors offer insight into the brain processes underlying relapse in psychosis.


Assuntos
Antipsicóticos/farmacologia , Disfunção Cognitiva/fisiopatologia , Progressão da Doença , Memória de Curto Prazo/fisiologia , Transtornos Psicóticos/fisiopatologia , Estresse Psicológico/fisiopatologia , Adulto , Antipsicóticos/administração & dosagem , Método Duplo-Cego , Feminino , Humanos , Masculino , Prognóstico , Transtornos Psicóticos/tratamento farmacológico , Fumarato de Quetiapina/administração & dosagem , Fumarato de Quetiapina/farmacologia , Recidiva , Indução de Remissão , Fatores de Tempo , Adulto Jovem
6.
J Zool (1987) ; 299(2): 84-88, 2016 06.
Artigo em Inglês | MEDLINE | ID: mdl-27570375

RESUMO

The cooperative breeding hypothesis (CBH) states that cooperative breeding, a social system in which group members help to rear offspring that are not their own, has important socio-cognitive consequences. Thornton & McAuliffe (2015; henceforth T&M) critiqued this idea on both conceptual and empirical grounds, arguing that there is no reason to predict that cooperative breeding should favour the evolution of enhanced social cognition or larger brains, nor any clear evidence that it does. In response to this critique, Burkart & van Schaik (2016 henceforth B&vS) attempt to clarify the causal logic of the CBH, revisit the data and raise the possibility that the hypothesis may only apply to primates. They concede that cooperative breeding is unlikely to generate selection pressures for enhanced socio-cognitive abilities, but argue instead that the CBH operates purely through cooperative breeding reducing social or energetic constraints. Here, we argue that this revised hypothesis is also untenable because: (1) it cannot explain why resources so released would be allocated to cognitive traits per se rather than any other fitness-related traits, (2) key assumptions are inconsistent with available evidence and (3) ambiguity regarding the predictions leaves it unclear what evidence would be required to falsify it. Ultimately, the absence of any compelling evidence that cooperative breeding is associated with elevated cognitive ability or large brains (indeed data suggest the opposite is true in non-human primates) also casts doubt on the capacity of the CBH to explain variation in cognitive traits.

7.
Psychol Med ; 45(9): 1825-37, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25499574

RESUMO

BACKGROUND: Reduced cortical gray-matter volume is commonly observed in patients with psychosis. Cortical volume is a composite measure that includes surface area, thickness and gyrification. These three indices show distinct maturational patterns and may be differentially affected by early adverse events. The study goal was to determine the impact of two distinct obstetrical complications (OCs) on cortical morphology. METHOD: A detailed birth history and MRI scans were obtained for 36 patients with first-episode psychosis and 16 healthy volunteers. RESULTS: Perinatal hypoxia and slow fetal growth were associated with cortical volume (Cohen's d = 0.76 and d = 0.89, respectively) in patients. However, the pattern of associations differed across the three components of cortical volume. Both hypoxia and fetal growth were associated with cortical surface area (d = 0.88 and d = 0.72, respectively), neither of these two OCs was related to cortical thickness, and hypoxia but not fetal growth was associated with gyrification (d = 0.85). No significant associations were found within the control sample. CONCLUSIONS: Cortical dysmorphology was associated with OCs. The use of a global measure of cortical morphology or a global measure of OCs obscured important relationships between these measures. Gyrification is complete before 2 years and its strong relationship with hypoxia suggests an early disruption to brain development. Cortical thickness matures later and, consistent with previous research, we found no association between thickness and OCs. Finally, cortical surface area is largely complete by puberty and the present results suggest that events during childhood do not fully compensate for the effects of early disruptive events.


Assuntos
Traumatismos do Nascimento/epidemiologia , Córtex Cerebral/patologia , Retardo do Crescimento Fetal/epidemiologia , Substância Cinzenta/patologia , Hipóxia/epidemiologia , Transtornos Psicóticos/patologia , Adolescente , Adulto , Estudos de Casos e Controles , Humanos , Imageamento por Ressonância Magnética , Masculino , Tamanho do Órgão , Transtornos Psicóticos/epidemiologia , Fatores de Risco , Adulto Jovem
8.
Phys Rev Lett ; 112(9): 098001, 2014 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-24655279

RESUMO

We present results concerning the important role of system packing in the processes of density- and inelasticity-induced segregation in vibrofluidized binary granular beds. Data are acquired through a combination of experimental results acquired from positron emission particle tracking and simulations performed using the discrete particle method. It is found that segregation due to inelasticity differences between particle species is most pronounced in moderately dense systems, yet still exerts a significant effect in all but the highest density systems. Results concerning segregation due to disparities in particles' material densities show that the maximal degree to which a system can achieve segregation is directly related to the density of the system, while the rate at which segregation occurs shows an inverse relation. Based on this observation, a method of minimizing the time and energy requirements associated with producing a fully segregated system is proposed.

9.
J Acoust Soc Am ; 136(6): 3233, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25480070

RESUMO

Randomized stimulation and averaging (RSA) allows auditory evoked potentials (AEPs) to be recorded at high stimulation rates. This method does not perform deconvolution and must therefore deal with interference derived from overlapping transient evoked responses. This paper analyzes the effects of this interference on auditory brainstem responses (ABRs) and middle latency responses (MLRs) recorded at rates of up to 300 and 125 Hz, respectively, with randomized stimulation sequences of a jitter both greater and shorter than the dominant period of the ABR/MLR components. Additionally, this paper presents an advanced approach for RSA [iterative-randomized stimulation and averaging (I-RSA)], which includes the removal of the interference associated with overlapping responses through an iterative process in the time domain. Experimental results show that (a) RSA can be efficiently used in the recording of AEPs when the jitter of the stimulation sequence is greater than the dominant period of the AEP components, and (b) I-RSA maintains all the advantages of RSA and is not constrained by the restriction of a minimum jitter. The significance of the results of this study is discussed.


Assuntos
Estimulação Acústica , Tronco Encefálico/fisiologia , Potenciais Evocados Auditivos do Tronco Encefálico/fisiologia , Tempo de Reação/fisiologia , Vias Auditivas/fisiologia , Limiar Auditivo/fisiologia , Simulação por Computador , Eletroencefalografia , Psicoacústica , Distribuição Aleatória , Processamento de Sinais Assistido por Computador , Espectrografia do Som
10.
HIV Med ; 14 Suppl 3: 49-52, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24033905

RESUMO

OBJECTIVES: UK guidelines recommend routine HIV testing in general clinical settings when the local HIV prevalence is > 0.2%. During pilot programmes evaluating the guidelines, we used laboratory-based testing of oral fluid from patients accepting tests. Samples (n = 3721) were tested manually using the Bio-Rad Genscreen Ultra HIV Ag-Ab test (Bio-Rad Laboratories Ltd, Hemel Hempstead, UK). This was a methodologically robust method, but handling of samples was labour intensive. We performed a validation study to ascertain whether automation of oral fluid HIV testing using the fourth-generation HIV test on the Abbott Architect (Abbott Diagnostics, Maidenhead, UK) platform was possible. METHODS: Oral fluid was collected from 143 patients (56 known HIV-positive volunteers and 87 others having contemporaneous HIV serological tests) using the Oracol+ device (Malvern Medicals, Worcester, UK). Samples were tested concurrently: manually using the Genscreen Ultra test and automatically on the Abbott Architect. RESULTS: For oral fluid, the level of agreement of results between the platforms was 100%. All results agreed with HIV serology. The use of the Oracol+ device produced high-quality samples. Subsequent field use of the test has shown a specificity of 99.97% after nearly 3000 tests. CONCLUSIONS: Laboratory-based HIV testing of oral fluid requires less training of local staff, with fewer demands on clinical time and space than near-patient testing. It is acceptable to patients. The validation exercise and subsequent clinical experience support automation, with test performance preserved. Automation reduces laboratory workload and speeds up the release of results. Automated oral fluid testing is thus a viable option for large-scale HIV screening programmes.


Assuntos
Sorodiagnóstico da AIDS/métodos , Anticorpos Anti-HIV/análise , Infecções por HIV/diagnóstico , Programas de Rastreamento/métodos , Sorodiagnóstico da AIDS/normas , Infecções por HIV/imunologia , HIV-1 , HIV-2 , Humanos , Programas de Rastreamento/economia , Programas de Rastreamento/normas , Reprodutibilidade dos Testes , Saliva/imunologia , Saliva/virologia
11.
Res Sq ; 2023 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-37693576

RESUMO

Background: Cardiovascular disease (CVD) is a complex disease, and genetic factors contribute individually or cumulatively to CVD risk. While African American women and men are disproportionately affected by CVD, their lack of representation in genomic investigations may widen disparities in health. We investigated the associations of cardiometabolic polygenic risk scores (PRSs) with CVD risk in African Americans. Methods: We used the Jackson Heart Study, a prospective cohort study of CVD in African American adults and the predicted atherosclerotic cardiovascular disease (ASCVD) 10-year risk. We included 40-79 years old adults without a history of coronary heart disease (CHD) or stroke at baseline. We derived genome-wide PRSs for systolic blood pressure (SBP), diastolic blood pressure (DBP), total cholesterol, LDL cholesterol, hemoglobin A1c (HbA1c), triglycerides, and C-reactive protein (CRP) separately for each of the participants, using African-origin UK Biobank participants' genome-wide association summary statistics. We estimated the associations between PRSs and 10-year predicted ASCVD risk adjusting for age, sex, study visit date, and genetic ancestry using linear and logistic regression models. Results: Participants (n=2,077) were 63% female and 66% never-smokers. They had mean (SD) 56 (10) years of age, 127.8 (16.3) mmHg SBP, 76.3 (8.7) mmHg DBP, 200.4 (40.2) mg/dL total cholesterol, 51.7 (14.7) mg/dL HDL cholesterol, 127.2 (36.7) mg/dL LDL cholesterol, 6.0 (1.3) mmol/mol HbA1c, 108.9 (81.7) mg/dL triglycerides and 0.53 (1.1) CRP. Their median (interquartile range) predicted 10-year predicted ASCVD risk was 8.0 (4.0-15.0). Participants in the >75th percentile for HbA1c PRS had 1.42 percentage-point greater predicted 10-year ASCVD risk (1.42 [95% CI: 0.58-2.26]) and higher odds of ≥10% predicted 10-year ASCVD risk (OR: 1.46 [95% CI: 1.03-2.07]) compared with those in the <25th percentile for HbA1c PRS. Participants in the >75th percentile for SBP PRS had higher odds of ≥10% predicted 10-year ASCVD risk (OR: 1.52 [95% CI: 1.07-2.15]) compared with those in the <25th percentile for SBP PRS. Conclusion: Among 40-79 years old African Americans without CHD and stroke, higher PRSs for HbA1c and SBP were associated with CVD risk. PRSs may help stratify individuals based on their clinical risk factors for CVD early prevention and clinical management.

12.
J Neurophysiol ; 107(5): 1301-12, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22157117

RESUMO

The medial olivocochlear (MOC) bundle reduces the gain of the cochlear amplifier through reflexive activation by sound. Physiological results indicate that MOC-induced reduction in cochlear gain can enhance the response to signals when presented in masking noise. Some previous studies suggest that this "antimasking" effect of the MOC system plays a role in speech-in-noise perception. The present study set out to reinvestigate this hypothesis by correlating measures of MOC activity and speech-in-noise processing across a group of normal-hearing participants. MOC activity was measured using contralateral suppression of otoacoustic emissions (OAEs), and speech-in-noise processing was measured by measuring the effect of noise masking on performance in a consonant-vowel (CV) discrimination task and on auditory brain stem responses evoked by a CV syllable. Whereas there was a significant correlation between OAE suppression and both measures of speech-in-noise processing, the direction of this correlation was opposite to that predicted by the antimasking hypothesis, in that individuals with stronger OAE suppression tended to show greater noise-masking effects on CV processing. The current results indicate that reflexive MOC activation is not always beneficial to speech-in-noise processing. We propose an alternative to the antimasking hypothesis, whereby the MOC system benefits speech-in-noise processing through dynamic (e.g., attention- and experience-dependent), rather than reflexive, control of cochlear gain.


Assuntos
Estimulação Acústica/métodos , Cóclea/fisiologia , Ruído , Núcleo Olivar/fisiologia , Percepção da Fala/fisiologia , Adulto , Potenciais Evocados Auditivos do Tronco Encefálico/fisiologia , Feminino , Humanos , Masculino , Tempo de Reação/fisiologia , Fala/fisiologia , Adulto Jovem
13.
Br J Cancer ; 107(6): 937-46, 2012 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-22850552

RESUMO

BACKGROUND: Few epidemiological studies have prospectively investigated preoperative and surgical risk factors for acute postoperative pain after surgery for breast cancer. We investigated demographic, psychological, pain-related and surgical risk factors in women undergoing resectional surgery for breast cancer. METHODS: Primary outcomes were pain severity, at rest (PAR) and movement-evoked pain (MEP), in the first postoperative week. RESULTS: In 338 women undergoing surgery, those with chronic preoperative pain were three times more likely to report moderate to severe MEP after breast cancer surgery (OR 3.18, 95% CI 1.45-6.99). Increased psychological 'robustness', a composite variable representing positive affect and dispositional optimism, was associated with lower intensity acute postoperative PAR (OR 0.63, 95% CI 0.48-0.82) and MEP (OR 0.71, 95% CI 0.54-0.93). Sentinel lymph node biopsy (SLNB) and intraoperative nerve division were associated with reduced postoperative pain. No relationship was found between preoperative neuropathic pain and acute pain outcomes; altered sensations and numbness postoperatively were more common after axillary sample or clearance compared with SLNB. CONCLUSION: Chronic preoperative pain, axillary surgery and psychological robustness significantly predicted acute pain outcomes after surgery for breast cancer. Preoperative identification and targeted intervention of subgroups at risk could enhance the recovery trajectory in cancer survivors.


Assuntos
Adaptação Psicológica , Neoplasias da Mama/psicologia , Neoplasias da Mama/cirurgia , Dor Crônica/complicações , Mastectomia/efeitos adversos , Dor Pós-Operatória/epidemiologia , Dor Pós-Operatória/etiologia , Temperamento , Adulto , Idoso , Carcinoma Ductal de Mama/psicologia , Carcinoma Ductal de Mama/cirurgia , Análise Fatorial , Feminino , Humanos , Incidência , Modelos Logísticos , Mastectomia/métodos , Mastectomia/psicologia , Pessoa de Meia-Idade , Análise Multivariada , Medição da Dor , Dor Pós-Operatória/psicologia , Valor Preditivo dos Testes , Período Pré-Operatório , Estudos Prospectivos , Biópsia de Linfonodo Sentinela/efeitos adversos , Índice de Gravidade de Doença
14.
HIV Med ; 13(7): 416-26, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22413900

RESUMO

OBJECTIVES: Community HIV testing represents an opportunity for diagnosing HIV infection among individuals who may not have contact with health services, especially in hard-to-reach groups. The aim of this review was to assess the evidence for feasibility, acceptability and effectiveness of HIV testing strategies in community settings in resource-rich countries. METHODS: The PubMed database was searched for English language studies of outreach HIV testing in resource-rich countries. Studies were included if they reported one of the following outcome measures: uptake of testing; seropositivity; client acceptability; or provider acceptability. RESULTS: Forty-four studies were identified; the majority took place in the USA and targeted men who have sex with men. Uptake of HIV testing varied between 9 and 95% (in 14 studies). Seropositivity was ≥ 1% in 30 of 34 studies. In 16 studies the proportion of patients who received their test results varied from 29 to 100% and rapid testing resulted in a higher proportion of clients receiving their results. Overall, client satisfaction with community HIV testing was high. However, concern remained over confidentiality, professional standards and the need for post-test counselling. Staff reported positive attitudes towards community testing. CONCLUSIONS: In the majority of studies, the reported seropositivity was higher than 1/1000, the threshold deemed to be cost-effective for routinely offering testing. Rapid testing improved the return of HIV test results to clients. HIV testing in outreach settings may be important in identifying undiagnosed infections in at-risk populations, but appropriate data to evaluate these initiatives must be collected.


Assuntos
Serviços de Saúde Comunitária/organização & administração , Aconselhamento/métodos , Países Desenvolvidos/estatística & dados numéricos , Soropositividade para HIV/diagnóstico , Homossexualidade Masculina , Programas de Rastreamento/métodos , Aceitação pelo Paciente de Cuidados de Saúde/estatística & dados numéricos , Diagnóstico Precoce , Medicina Baseada em Evidências , Feminino , Soropositividade para HIV/epidemiologia , Homossexualidade Masculina/estatística & dados numéricos , Humanos , Masculino , Comportamento Sexual , Estados Unidos/epidemiologia
15.
Phys Rev Lett ; 109(8): 081101, 2012 Aug 24.
Artigo em Inglês | MEDLINE | ID: mdl-23002733

RESUMO

In this paper we present in situ satellite data, theory, and laboratory validation that show how small-scale collisionless shocks and minimagnetospheres can form on the electron inertial scale length. The resulting retardation and deflection of the solar wind ions could be responsible for the unusual "lunar swirl" patterns seen on the surface of the Moon.

16.
Phys Chem Chem Phys ; 14(13): 4365-73, 2012 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-22270868

RESUMO

Microporous materials have a great importance in catalysis, delivery, storage and separation in terms of their performance and efficiency. Most microporous materials are comprised of inorganic frameworks, while thermally rearranged (TR) polymers are a microporous organic polymer which is tuned to optimize the cavity sizes and distribution for difficult separation applications. The sub-nano sized microcavities are controlled by in situ thermal treatment conditions which have been investigated by positron annihilation lifetime spectroscopy (PALS). The size and relative number of cavities increased from room temperature to 230 °C resulting in improvements in both permeabilities and selectivities for H(2)/CO(2) separation due to the significant increase of gas diffusion and decrease of CO(2) solubility. The highest performance of the well-tuned TR-polymer membrane was 206 Barrer for H(2) permeability and 6.2 of H(2)/CO(2) selectivity, exceeding the polymeric upper bound for gas separation membranes.


Assuntos
Dióxido de Carbono/química , Membranas Artificiais , Polímeros/química , Temperatura , Hidrogênio/química , Tamanho da Partícula , Polímeros/síntese química , Porosidade , Propriedades de Superfície
17.
Cytopathology ; 23(3): 150-60, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21366734

RESUMO

OBJECTIVE: To identify factors associated with default from follow-up cervical cytology tests. METHODS: A cohort study was conducted involving 2166 women, aged 20-59, with recent low-grade cervical cytology taken within the NHS Cervical Screening Programmes in Scotland and England, and managed by 6-monthly cytology in primary care. For the first (6-month) and second (12-month) surveillance cytology tests separately, women were categorized as 'on-time attendees' (attended ≤6 months of test being due), 'late attendees' (attended greater than 6 months after test was due) or 'non-attendees' (failed to attend). Multivariate odds ratios (ORs) were computed for factors associated with late and non-attendance. RESULTS: For the first surveillance test, risk of non-attendance was significantly higher in younger women, those without post-secondary education, and non-users of prescribed contraception. Factors significantly associated with late attendance for the first test were the same as for non-attendance, plus current smoking and having children. The most important predictor of non-attendance for the second surveillance test was late attendance for the first test (OR = 9.65; 95% CI, 6.60-16.62). Non-attendance for the second test was also significantly higher among women who were younger, smokers and had negative cytology on the first surveillance test. Late attendance for the second surveillance test was higher in women who were younger, smokers, had children and attended late for the first test. CONCLUSIONS: Women at highest risk of default from follow-up cytology tend to be young, smoke, lack post-secondary education, and have defaulted from a previous surveillance appointment. Tackling default will require development of targeted strategies to encourage attendance and research to better understand the reasons underpinning default.


Assuntos
Colo do Útero/patologia , Perda de Seguimento , Vigilância da População/métodos , Neoplasias do Colo do Útero/diagnóstico , Adulto , Fatores Etários , Atitude Frente a Saúde , Estudos de Coortes , Biologia Computacional , Detecção Precoce de Câncer/métodos , Inglaterra , Feminino , Seguimentos , Humanos , Estilo de Vida , Pessoa de Meia-Idade , Razão de Chances , Fatores de Risco , Escócia , Fumar/psicologia , Neoplasias do Colo do Útero/patologia , Neoplasias do Colo do Útero/prevenção & controle , Adulto Jovem
18.
Phys Rev E ; 106(5-1): 054614, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36559476

RESUMO

It is well known that granular mixtures that differ in size or shape segregate when sheared. In the past, two mechanisms have been proposed to describe this effect, and it is unclear if both exist. To settle this question, we consider a bidisperse mixture of spheroids of equal volume in a rotating drum, where the two mechanisms are predicted to act in opposite directions. We present evidence that there are two distinct segregation mechanisms driven by relative overstress. Additionally, we showed that, for nonspherical particles, these two mechanisms (kinetic and gravity) can act in different directions leading to a competition between the effects of the two. As a result, the segregation intensity varies nonmonotonically as a function of aspect ratio (AR), and, at specific points, the segregation direction changes for both prolate and oblate spheroids, explaining the surprising segregation reversal previously reported. Consistent with previous results, we found that the kinetic mechanism is dominant for (almost) spherical particles. Furthermore, for moderate aspect ratios, the kinetic mechanism is responsible for the spherical particles' segregation to the periphery of the drum, and the gravity mechanism plays only a minor role. Whereas, at the extreme values of AR, the gravity mechanism notably increases and overtakes its kinetic counterpart.

19.
Rev Sci Instrum ; 93(9): 093509, 2022 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-36182454

RESUMO

Neutron flux measurements are important in fusion devices for both safety requirements and physics studies. A new system has been built for the Mega-Amp Spherical Tokamak Upgrade (MAST Upgrade) that provides neutron count, DC, and Campbell mode measurements for a 1 µs period at 1 MHz. The acquisition system uses a Red Pitaya board to sample current from two fission chambers mounted on the side of the MAST-U vessel. The system-on-chip design of the Zynq-7020 on the Red Pitaya also allows a web server implementation using Flask for data retrieval and diagnostic configuration over the MAST Upgrade network.

20.
Br J Cancer ; 104(2): 255-64, 2011 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-21179033

RESUMO

BACKGROUND: The debate continues regarding the best management for women with low-grade abnormal cervical cytology attending colposcopy. We compared psychosocial outcomes of alternative management policies in these women. METHODS: In all, 989 women, aged 20-59 years, with low-grade abnormal cytology, were randomised to immediate large loop excision (LLETZ) or two to four targeted punch biopsies taken immediately with recall for LLETZ if these showed cervical intra-epithelial neoplasia 2/3. At 6 weeks after the last procedure, women completed the hospital anxiety and depression scale (HADS) and the impact of event scale (IES). At 12, 18, 24 and 30 months post recruitment, women completed the HADS and process outcome specific measure (POSM). Prevalence of significant depression (≥ 8), significant anxiety (≥ 11) and distress (≥ 9) and median POSM scores were compared between arms. Multivariate odds ratios (ORs) for immediate LLETZ vs biopsy and recall were computed. RESULTS: Over the entire follow-up, there was no significant difference between arms in cumulative prevalence or risk of significant depression (OR=0.78, 95% CI 0.52-1.17) or significant anxiety (OR=0.83, 95% CI 0.57-1.19). At 6 weeks post procedure, distress did not differ significantly between arms. At later time points, 8-11% had significant depression and 14-16% had significant anxiety but with no differences between arms. The POSM scores did not differ between the arms. CONCLUSIONS: There is no difference in long- or short-term psychosocial outcomes of immediate LLETZ and punch biopsies with selective recall.


Assuntos
Colposcopia , Displasia do Colo do Útero/psicologia , Adulto , Ansiedade/psicologia , Biópsia , Depressão/psicologia , Feminino , Humanos , Pessoa de Meia-Idade , Análise Multivariada , Displasia do Colo do Útero/diagnóstico , Displasia do Colo do Útero/patologia , Displasia do Colo do Útero/terapia
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